Refer to the exhibit.
Host A can communicate with Host B but not with Hosts C or D. How can the network
administrator solve this problem?
A.
Configure Hosts C and D with IP addresses in the 192.168.2.0 network.
B.
Install a router and configure a route to route between VLANs 2 and 3.
C.
Install a second switch and put Hosts C and D on that switch while Hosts A and B remain on
the original switch.
D.
Enable the VLAN trunking protocol on the switch.
http://www.webopedia.com/DidYouKnow/Hardware_Software/router_switch_hub.asp
Router –
A device that forwards data packets along networks. A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP.s network. Routers are located at gateways, the places where two or more networks connect. Routers use headers and forwarding tables to determine the best path for forwarding the packets, and they use protocols such as ICMP to communicate with each other and configure the best route between any two hosts.
Switch –
In networks, a device that filters and forwards packets between LAN segments. Switches operate at the data link layer (layer 2) and sometimes the network layer (layer 3) of the OSI Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs.
A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, or office building.[1] A local area network is contrasted in principle to a wide area network (WAN), which covers a larger geographic distance and may involve leased telecommunication circuits, while the media for LANs are locally managed.
A virtual LAN (VLAN) is any broadcast domain that is partitioned and isolated in a computer network at the data link layer (OSI layer 2)
Hubs
Hubs, also known as repeaters, operate on layer-1 (I.e. the physical layer).
Hubs cannot process layer-2 or layer-3 traffic. Layer-2 deals with hardware addresses and layer-3 deals with logical (IP) addresses. So, hubs cannot process information based on MAC or IP addresses.
Hubs cannot even process data based on whether it is a uni-cast, broadcast or multi-cast data.
All that a hub does is that it transfers data to every port excluding the port from where data was generated.
Switches
Switches are network devices that operate on layer-2 of OSI.
Switches operate on hardware addresses MAC to transfer data across devices connected to them.
The reason switches are known as intelligent hubs is because they build address table in hardware to keep track of different hardware addresses and the port to which each hardware address is associated.
Routers
Routers are the network devices that operate at Layer-3 of OSI model.
As layer-3 protocols have access to logical address (IP addresses) so routers have the capability to forward data across networks.
Sometimes routers are also known as layer-3 switches.
Routers are far more feature rich as compared to switches.
Routers maintain routing table for data forwarding.
Switch –
As layer 2 protocols headers have no information about network of data packet so switches cannot forward data based or networks and that is the reason switches cannot be used with large networks that are divided in sub networks.